Holm Oak (Quercus ilex L.) canopy as interceptor of airborne trace elements and their accumulation in the litter and topsoil.

We investigated the role of urban Holm Oak (Quercus ilex L.) trees as an airborne metal accumulators and metals' environmental fate. Analyses confirmed Pb, Cd, Cu and Zn as a main contaminants in Siena's urban environment; only Pb concentrations decreased significantly compared to earlier surveys. Additionally, we determined chemical composition of tree leaves, litter and topsoil (underneath/outside tree crown) in urban and extra-urban oak stands. Most notably, litter in urban samples collected outside the canopy had significantly lower concentrations of organic matter and higher concentrations of Pb, Cu, Cd and Zn than litter collected underneath the canopy. There was a greater metals' accumulation in topsoil, in samples collected under the tree canopy and especially near the trunk ('stemflow area'). Thus, in urban ecosystems the Holm Oak stands likely increase the soil capability to bind metals.

Baseline element composition of foliose and fruticose lichens along the steep climatic gradient of SW Patagonia (Aisén Region, Chile).

Samples of foliose (Nephroma antarcticum) and fruticose (Usnea sp.) lichens were collected across a steep climatic and vegetation gradient in a remote, almost pristine region of SW Chilean Patagonia. Concentrations of major and trace elements in lichens from the rainforest were among the lowest ever reported worldwide for foliose and fruticose lichens and can be considered background levels for the region. The two lichen growth forms showed different elemental compositions mainly due to the greater capacity of foliose thalli to intercept elements from windborne and canopy-leached particles. The patterns of spatial variation in the chemical composition of lichens were effectively explained by statistical methods and reflected the different availability of wet and dry deposition along the steep climatic gradient. Baseline values established for N. antarcticum samples growing in temperate Nothofagus forests were therefore distinct from those of samples growing in more open, drier habitats. The fruticose Usnea sp. showed a higher affinity for atmophile Hg, low concentrations of lithophilic elements, and the same baseline composition whether from temperate forests or from dry, barren environments. The provided background and baseline values against which variations can be measured will be useful in the early detection of local or regional climatic and environmental change, especially in view of the planned construction of hydropower dams under the recently approved HidroAysén Project.

The effects of the electric fields on hydrogels to achieve antitumoral drug release.

The achievement of electrochemotherapy was obtained using electrodes covered with guar gum (GG) hydrogel swollen in a sulfate bleomycin solution. The bleomycin delivery into the plasma membranes of cancer cells occurs only when field strength (V/cm) was applied, decreasing the drug contact with healthy tissues. The effect of the delivered bleomycin at different concentrations was examined on tumoral mouse fibroblast (NIH3T3) and human coronary artery endothelial cells. The GG hydrogel released the drug only when the field strength was applied and the amount depended on the electromotive force. Consequently, cellular survival depended on the field strength. Moreover in vitro results showed a bigger cellular mortality of the NIH3T3 compared with endothelial cells. The best parameters to be utilized in electrochemotherapy were ascertained.

US, MRCP, CCT and ERCP: a comparative study in 131 patients with suspected biliary obstruction.

BACKGROUND: Recent years have witnessed a rapid and continuous evolution in the diagnosis of biliary obstructive disease. Traditional methodologies, such as US (ultrasonography), CT (computed tomography), ERCP (endoscopic retrograde cholangiopancreatography) and PTC (percutaneous transhepatic cholangiography), have been supplemented by MRCP (magnetic resonance cholagiopancreatography) and CCT (cholangio computed tomography) The purpose of our study was to compare the reliability of diagnostic US, MR and other imaging techniques in intrinsic biliary obstructive disease. MATERIAL/METHODS: Between June 1999 and July 2003 we conducted a prospective study on 131 patients--60 males and 71 females--ranging in age from 37 to 79 years, with clinical features of biliary obstructive disease. Imaging studies were done on each patient using several different techniques. The US, MRCP, CCT and ERCP results were read by radiologists blinded to other imaging findings. RESULTS: US is generally accurate in diagnostic imaging of obstructive biliary disease. MRCP and CCT are significantly more accurate only in completing the staging of malignant stenosis. CONCLUSIONS: If the suspicion posed by clinical and laboratory findings is not confirmed at US, the diagnosis must be achieved with the aid of MRCP or--where MRCP does not provide a diagnosis--CCT, so as to select candidates for therapeutic ERCP, PTC or surgery. If laboratory and clinical findings are supported by US, ERCP is required for therapeutic purposes, or--if necessary--surgery is performed.

Treatment of large hepatocellular carcinoma: comparison between techniques and long term results.

PURPOSE: The aim of this study was to compare results over time of Transcatheter Arterial Chemo Embolization (TACE), Percutaneous Ethanol Injection (PEI), Laser Thermal Ablation (LTA) and combined therapy of large Hepatocellular Carcinoma (HCC). MATERIALS AND METHODS: Between 1995 and 2003, 89 cirrhosis patients (51 Child-Pugh A, 38 Child-Pugh B) with at least one nodule of HCC =/> 40 mm, were included in this randomized study; 21 were treated with TACE, 20 with PEI, 29 with LTA and 19 with combined therapy. The total number of HCC nodules was 92 with a mean diameter of 52.9 mm. RESULTS: No major complication occurred in all procedures. CT scan showed that complete necrosis was achieved in 83% of treated nodules (76 out of 92); as a whole, the disease relapsed in 18 (20.2%) patients (disease free interval being 18.2+/-9.4 months). The cumulative survival rates were 69.6%, 25.1% and 9.8% at 12, 36 and 60 months respectively. Univariate analysis of survival showed statistically significant differences in the comparison between Child-Pugh A group vs B (p<0.0001) and between single nodule vs multiple (p=0.0019). Patients subjected to combined therapy and LTA showed a statistically significant longer survival than those treated with TACE and PEI. CONCLUSIONS: LTA proves to be the most effective treatment for HCC < 50 mm, combined therapy is the best choice for nodules =/> 50 mm since complete necrosis is achieved in almost all cases and better total survival in the treated patients.